Akademik Veri Yönetim Sistemi
International Journal of Bio-Technology and Research (IJBTR), cilt.6, sa.4, ss.7-16, 2016 (Hakemli Dergi)
Brassinosteroids (BRs) are steroidal plant hormones that influence varied growth and development processes
such as germination of seeds, flowering, senescence and abscission. The effect of epibrassinolide (eBL), one of the most
active brassinosteroids, on senescencing cotyledons of Glycine max L. seedlings, which represent epigeic germination,
has been investigated in this study. The process of senescence was examined by spraying eBL solutions of 10-11 M and
10-9 M and 2,3,5-triiodobenzoic acid (TIBA), an inhibitor of auxin transport, to the 12 days-old seedlings. eBL
(especially 10-9 M) was observed to have induced senescence, while it has delayed senescence when applied with TIBA
together. These observations were confirmed with the measurements of total chlorophyll and protein amounts, and rate
of peroxidase activity. One has discussed that combined brassinosteroid and TIBA, the former being known to work
with auxin synergistically and the latter being an inhibitor of auxin transport, do not affect senescence but
brassinosteroids accelerate senescence in presence of auxin. As a result, one may think that eBL and auxin together
function as a senescence signal.
KEYWORDS: Brassinosteroids, Epibrassinolide, Sequential Leaf Senescence, TIBA, Glycine Max